• Journal of Power System Engineering
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• v.16 no.1
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• pp.91-97
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• 2012

It is being accelerated to develop environment-friendly vehicles to solve problems on the energy and environment of earth. The electric driving motor commonly installed in these vehicles has the excellent control capability such as fast response and accurate generation to torque control command. Especially, in-wheel motor has the additional merit such as independently driving each wheel in vehicle. Recently, being developed various control algorithm to enhance the safety and stability of vehicle motion using actively the merits of in-wheel motor. In addition to that, being issued the possibility of enhancing the ride comfort and attitude of vehicle motion such as pitching and rolling. In this paper, investigate the theoretical relationship between the braking/driving force and the motion of sprung mass of vehicle and propose the control method to enhance the ride comfort and attitude of vehicle motion. The proposed control method is proved through the simulation with vehicle model provided by TruckSim software which is commercial one and specializes in vehicle dynamics.

• The Journal of Fisheries Business Administration
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• v.40 no.2
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• pp.27-48
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• 2009

The objective of this paper is to estimate consumer's marginal willingness to pay(MWTP) for cold chain system attributes of mackerel using choice experiment questionnaires. The survey data were analyzed by conjoint analysis method with multinominal logit model. The five cold chain system attributes with $2{\sim}4$ attribute levels were considered : low temperature safekeeping of fishing boats, a kind of transport truck and packing box, using degree of low temperature facility in distribution, mackerel price per fish(1kg). At least 827 people were asked to participate in the survey. The major findings and implications of this study can be summarized as follows : The estimated multinominal logit model is statistically significant and the total consumers willingness to pay for the improved cold chain system attributes is 6,476 won (per kg). Compared with the base price(2,500 won/kg), the estimated MWTP is 2.5 times higher than the base price. Therefore, the consumer has a willingness to pay for the fresh and safe fish products, even though more money is paid. To satisfy the consumer's needs, cold chain system is necessary in point of long-term. In this reason, The government's policy support is needed for promoting cold chain system in fishery, and a master plan should be prepared.

• Geophysics and Geophysical Exploration
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• v.23 no.4
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• pp.230-242
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• 2020

We performed a magnetotelluric (MT) survey to delineate the geological structures below the depth of 20 km in the Gyeongju area where an earthquake with a magnitude of 5.8 occurred in September 2016. The measured MT data were severely distorted by electrical noise caused by subways, power lines, factories, houses, and farmlands, and by vehicle noise from passing trains and large trucks. Using machine-learning methods, we classified the MT time series data obtained near the railway and highway into two groups according to the inclusion of traffic noise. We applied three schemes, stochastic gradient descent, support vector machine, and random forest, to the time series data for the highspeed train noise. We formulated three datasets, Hx, Hy, and Hx & Hy, for the time series data of the large truck noise and applied the random forest method to each dataset. To evaluate the effect of removing the traffic noise, we compared the time series data, amplitude spectra, and apparent resistivity curves before and after removing the traffic noise from the time series data. We also examined the frequency range affected by traffic noise and whether artifact noise occurred during the traffic noise removal process as a result of the residual difference.

• Journal of Industrial Technology
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• v.22 no.A
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• pp.169-176
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• 2002

The purpose of this paper is to investigate for strain measurement of concrete pavement slab at field. The early-age behaviors of concrete pavement were measured using the strain gages. From the static and dynamic wheel loading tests, the outputs from each gages were recorded. The measured data, also, was compared to those from finite element analysis. The static wheel loading tests were performed in twice, and the dynamic wheel loading tests were performed at the speed 10km-50km. The results could be summarized as follows: To embed the strain gage accurately and stably in concrete pavement, a chair and protective box must be used. The protective box must not be affected from the outside vibrating. From the results of early-age stram measurement, it was found that the strain varied at the maximum value of $180{\mu}{\varepsilon}$ From the results of static wheel loading tests, A1, A2 and B gages generally developed a consistent tendency When comparing the results from the measured at field and the calculated by FEM analysis, the data of A1 and B gages were similar to that from theory. The values from the field test were generally higher than that from the theory. From the results of dynamic wheel loading tests, it was known that the measured strain at field became smaller as the truck speed became faster, Indicating the maximum at the range of $12{\sim}13{\mu}{\varepsilon}$.

• Journal of Environmental Science International
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• v.17 no.4
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• pp.397-403
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• 2008

The purpose of this study is to investigate weighted compaction density according to a leading density in truck, a compaction density of solid waste and composition ratios of solid waste fur calculation of a capacity of the landfill sites. The experiments for calculations of in-place density at landfill site have been conducted in S landfill site at B City. The size of vessel for measuring the compaction density was $1m^3(1m{\times}1m{\times}1m)$. The experiment tests have been carried out methods (1 time for bulldozer and 4 times for compactor) that do contain all of specification at the landfill site. Average of the loading density at the landfill site was $0.264\;ton/m^3$ ($0.113{\sim}0.487\;ton/m^3$). When the loading density for each compositions was compared, the composition of the highest average loading density ($0.474\;ton/m^3$) was miscellaneous wastes. The composition of the lowest average loading density ($0.120 ton/m^3$) was general solid waste. The reported results indicated that the compaction density at the landfill site was $0.538\;ton/m^3$, which was calculated with weighted incoming ratios of compositions. The ranges of the density for each composition were from $0.021\;ton/m^3$ to $0.221\;ton/m^3$. When the compaction density for each composition was compared, the composition with the highest average compaction density ($0.221\;ton/m^3$) was miscellaneous wastes. The composition with the lowest average compaction density ($0.021\;ton/m^3$) was general solid wastes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1523-1531
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• 2011

Multi-axle driving vehicle are favored for military use in off road operations because of their high mobility on extreme terrains and obstacles. Especially, Military Vehicle needs an ability to driving on hills of 60% angle slope. This paper presents the improvement of the ability of hill climbing for 6WD/6WS vehicle through the optimal tire force distribution method. From the driver's commands, the desired longitudinal force, the desired lateral force, and the desired yaw moment were obtained for the hill climbing of vehicle using optimal tire force distribution method. These three values were distributed to each wheel as the torque based on optimal tire force distribution method using friction circle and cost function. To verify the performance of the proposed algorithm, the simulation is executed using TruckSim software. Two vehicles, the one the proposed algorithm is implemented and the another the tire's forces are equivalently distributed, are compared. At the hill slop, the ability to driving on hills is improved by using the optimum tire force distribution method.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.8 no.2
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• pp.1-5
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• 2002

In order to improve the load efficiency of pallets and trucks for agricultural products, various transport package sizes have been analyzed by modular coordination process. From the results, the load efficiency on pallet was 99.8 percent when size was 550 by 366 mm and 366 by 275 mm. Load efficiency of standard pallet(1100 by 1100mm) was 93.6% for truck with 11 tons load capacity while as low as 41.1% for 2.5 ton trucks. Like any other products, this study proved that trucks with more than 8 tons of capacity were highly recommended for transportation of agricultural products.